Process of fireproofing wood.



Patenten' Aug. E; HQUL df. EisLEra. PROCESS 0F HBEPRDFING w00t?.

(Application led Feb. 12, 1900.)

(Snocimens.)

Dn nu Tl N.. rr. V N

WITNESSES:

ATTUR N EYS UNITED STATES.

PATENT OFFICE.

lIOSEPH F. GEISLER, OF NEW YORK, N. Y., ASSIGNOR 'IO THE AMERICAN WOOD FIREPROOFING COMPANY, OF SAME PLACE.

/PROCESS OF FIREPROOFING WOOD..

SPECIFICATION forming part of Letters Patent No. 679,739, dated August 6, 1901. Application filed February 12, 1900. Serial No. 5,034. (Specimens.)

T all whom, t may concern,.-

Be it known that JOSEPH F. GnisLnn, a

i citizen of the United States, residing at New York, in the county of New York and State of New York, have invented a certain new and useful Process for Fireproon g Wood and other Combustible Substances; and I do hereby declare the following to be a full, clear, and enact description ofthe invention, such as will enable others skilled in the art to 'which it appertains to make and use the same.

My invention relates to a process of fireproongwood and other combustible substances; and it consists in the novel steps of the process employed.4

The objects ofmy invention are to decrease 'the cost and increase the eiticiency of the 'treatment of wood and other combustible substances for the purpose of rendering them ,'lreprool, to prevent deliquescence of the 'salts used after they have been applied, and tgseal such salts into the pores of the Wood in an eectual manner. These objects are attained in the process herein described, an apparatus to be used in carrying out which is shown in the accompanying drawing, formihga'part of this specification.

' 'Infmy process I impregnato the Wood or other substance treated with a solution oontaining one or more ammonium salts, such as ammonium sulfato, phosphate, or tungstate, and also containing casein. I then subject thewood to the action of formaldehyde gas or'carbonic acid, which renders insoluble or coagiilatfes the casein, thereby sealing within the pones of the wood the fireprooing salts.

In erd'er to neutralize possible acidity of the o designates avacuum-l of other substances of a combustible nature may be carried on in the same manner.

Before the treatment of the wood is begun a sample of it is tested to determine the amount of moisture the wood is capable of absorbing. For this purpose it may be placed within a suitable tank and heated therein to a temperature ot from 100o to 110 Fahrenheit,a high vacuum being maintained. Nhen the vacuum remains constant for from one and a half to three hours, the tank may be allowed to fill with water, and after the wood has absorbed nearly as much water as it is capable of absorbing without the application of pressure a pressure of from one hundred -to one hundred and fty pounds to the square inch is applied and maintained until the pressure remains constant without further operation of the pump. .The wood is then removed from the tank and weighed. I f the sample shows an increase in weight within ninety per cent. of what experience shows to be the maximum increase in weight which it is practicable to obtain for'the particular variety of wood `treated, it is deemed suitable for treatment Without steaming; otherwise it must be steamed to some extent at least. For

dry white pine an increase in weight of one i hundred and eighty-five per cent. is sufficient. The wood to be iireproofed is then placed Within the tank a, the tank closed, and a high vacuum is produced in'the tank by means of the vacuum-pump. A quantity of ammoniagas or concentrated aqua-ammonia is then drawn into the cylinder and the ammonia al-V lowed to permeate the wood. After a time the vacuum is broken by drawing air through the water containing ammonia and having a temperature of about 130o Fahrenheit, thus charging the inrushing air with both moisture andammonia. When atmospheric pressure has been established in the tank a by the admission of air in this manner, steam is slowly passed through the coils b to raise the tem- 120c to 140o Fahrenheit. This temperature and the resulting pressure are maintained for a half-hour or more, according to the size of the timber treated, until the ammonia has penetrated into the heart of the wood. If the preliminary test above mentioned has perature of the contents of the tank to from x shown that the wood requires steaming, steam is introduced into the tank a. at this point, the temperature in such case rising higher than as above stated. After the treatment with ammonia or ammonia and steam is completed a vacuum is created in the tank, the ammonia-vapors withdrawn while creating this vacu um being collected in any customary manner. When the vacuum remains quite constant, the wood is ready to receive the impregnating solution.

The composition of the impregnating solution which I prefer to employ is as follows: sodium borate, .5 to 1.5 per cent.; ammonium sulfate, ten to fifteen per cent.; sodium sulfate, one to four per cent.; ammonium phosphate, two to six per cent.; sodium phosphate, two to siX per cent.; free ammonia, about .l per cent.; water to make up, one hundred per cent.; casein solution, sufficient o saturate. The casein solution, which, as above stated, is added to the solution containing ammonium `and sodium salts, is prepared by'dissolving casein and borax in water in the proportion of from four to five ounces of casein and two ounces of borax per gallon of water. The borax is used in the solution as a solvent and preservative of the casein. This solution is added to thefsolution of ammonium and sodium salts until the casein begins to cloud the solution or until, as known from previous experience, the s0- lution is saturated.

With the above-mentioned impregnating solution I preferably use from .2 to .5 per cent. of an oil emulsion. The oil chosen should be one which is liquid at 90 Fahrenheit, but congeals-at a temperature of from to 75 Fahrenheit. Such an oil mixture is easily produced by mixing cotton-seed oil with lard or tallow or by mixing a mineral oil with animal fat or paraffin. I may also use in connection with the impregnating solution and as a water-repellent from .2 to l per cent. of a soluble soap, preferably a potassium soap, the fatty acids of which are caused to separate in the dried impregnated wood by the action of carbonio-acid gas ory other gas having an acid reaction. These fatty acids act as water-repellents, and therefore serve to prevent water from reaching and so acting upon the iireproofing salts with which the wood is impregnated, and, if desired, the soap may be used instead of t-he casein.

The impregnation is accomplished by admitting the impregnating solution to the cylinder containing the-wood after a Vacuum has been produced therein, as above stated, and by applying a pressure of from one hundred to one hundred and fifty pounds to the square inch. This pressure is maintained for a period of from twelve to fortyeight hours, according to the Variety and thickness of the wood treated.V Twelve hours is usually sucient for wood an inch thick. When the l impregnation is complete,the Wood is allowed then liberating the fatty acid of the soap to dry and is then subjected to the action of formaldehyde gas or carbonic-acid gas, the wood being first subjected to a vacuum be fore the gaseous reagent is admitted to it. Formaldehyde gas, if used, renders the casein insoluble,and so causes it to seal the fireproofing salts into the pores of the wood. Carbonic-acid gas, if used, coagulates the casein, and so accomplishes the same purpose. -If the impregnating solution contained soap, as above described, carbonio-acid gas may be applied after the formaldehyde treatment to liberate the fattyacids from the soap, or the carbonio-acid treatment may be substituted for the treatment with formaldehyde,in which case the casein is coagulated and the fatty acids are liberated in one operation. Instead of carbonio-acid gas any other gas or vapor having an acid reaction may be used. The

treatment with formaldehyde or with car- 4 bonic-acid or other acid gas or Vapor should be continued for two hours or more, depending upon the thickness of the timber treated.

Instead of employing an impregnating solution containing a number of dierent salts of ammonium and sodium a solution of a single ammonium salt may be employed in connection with the casein; but a certain mixture of sodium salts with ammonium salts is preferred. Potassium salts may be substituted for the sodium salts, and the process herein describedof sealing a reprooiing agent into the pores of the wood by introducing casein and then coagulatingit or rendering it insoluble is equally applicable to the sealing into the pores of fibrous substances or other substances, whether Iireproofing agents or otherwise.

IOO

Having thus completely described my invention, what I claim, and desire to secure by Letters Patent, is-

1. The herein-described method of sealing into the pores of fibrous material substances with which such material is impregnated, which consists in introducing casein into such material, and then rendering the casein insoluble'.

2. The herein-described method of sealing into the pores of fibrous material substances with which 4such material is impregnated, which consists in introducing casein into such material, and then applying a gaseous reagent to render the casein insoluble.

3. The herein-described method of sealing into the pores of fibrous material substances with which such material is impregnated, which consists in introducing casein into such material, and then applying formaldehyde to render the casein insoluble.

4. The herein-described method of applying to fibrous material a Waterrepellent, which consists in impregnating such material With a solution containing a soluble soap, and

the action of an acid.

5. The herein-described method of applyingI to fibrous material a water 'f repellent,

IIO

IZO

which consists in impregnating such material with a solution containing a soluble soap, and then liberating the fatty acid of the soap by the action of a gas having an acid reaction.

6. The herein-described method of applying to fibrous material a water repellent, which consists in impregnating such material with a solution containing a soluble soap, and then liberating the fatty acid of the soap by the action of carbonio-acid gas.

7. The herein described process of fireproofing Wood and other fibrous substances, which consists in impregnating such substance With a reproofing material and With casein, and then rendering the casein insoluble.

8. The herein described process of fireproofing wood and other fibrous substances, which consists in impregnating such substance with a fireproofing material, wit-h an oil, and with casein, and then rendering the casein insoluble.

9. The herein-described process of fireproofing wood and other fibrous substances, which consists in impregnating Wood With a freproong material, with casein, and With a soluble soap, and then rendering the casein insoluble and liberating the fatty acid of the soap.

l0. The hereindescribed process of fireproofing Wood and other fibrous substances, Which consists in impregnating wood with a fireproofing material and with a soluble soap, and then liberating the fatty acid of the soap.

1l. The herein-described process of fireproofing wood and other fibrous substances, which consists in impregnating Wood with a solution containing ammonium salts and casein, and then rendering the casein insoluble.

l2. The herein-described process of fireproofing Wood and other fibroussubstances, which consists in impregnating wood with a solution containing ammonium and sodium sulfate, ammonium and sodium phosphate, and casein, and then rendering the casein insoluble. v

18. The herein-described process of introducing casein into the pores of Wood and other fibrous substances, and fixing the same therein, which consists in first neutralizing possible acidity of the substance treated with a gas or Vapor having an alkaline reaction, applying a solution containing casein, and then rendering the casein insoluble.

14. The herein-described process of fireproofing wood and other fibrous substances, which consists in first neutralizingpossible acidity of 'the substance treated with a gas or vapor having an alkaline reaction, then impregnating such substance with a fireproofing material and with casein, and then rendering the casein insoluble.

In testimony whereof I afhx my signature in the presence of two Witnesses.

JOSEPH F. GEISLER.

Witnesses:

H. M. MARBLE, A. H. PERLES. 

